Here are some cheats and special moves for Tony Hawks Pro Skater for the N64
PLAY AS OFFICER DICK
Get all 30 Tapes in the Career Mode.
Special Moves:
Assume the Position: Left, Left, C-Right
Yeehaw Frontflip: Down, Up, C-Right
Neckbreak Grind: Left, Right, C-Up

STATS AT 13 - WILL MAKE YOUR RIDERS STATS 13.
Enter any mode, press START to pause the game and hold the L Button. Then, press Up C, Left C, Left, Up, Down. The screen will shake if entered correctly.

STATS AT 10 WILL MAKE YOUR RIDERS STATS 10.
Enter any mode, press START to pause the game and hold the L Button. Then, press Up C, Left C,Left, Up, Down C. The screen will shake if entered correctly.

SLOW MOTION
Enter any mode, press START to pause the game and hold the L Button. Then, press Down, Down, Up C Right C, Left. The screen will shake if entered correctly.

ADD RESTART POINTS
Allows you to choose from a variety of locations to re-start the session. Enter any mode, press START to pause the game and hold the L Button. Then, press C-Left, C-Right, C-Down, Up, Down. The screen will shake if entered correctly.

SECRET CHARACTER
Unlocks Private Carrera, a female skateboarder. First, you have to unlock Officer Dick by earning all of the tapes in the Career Mode. Then, choose Officer Dick and enter any game mode. Press Start to Pause the game, hold the L Button and press C-Left, C-Down, C-Right, C-Down, Up, Right, Left. The next time you enter the Player Select screen, Private Carrera will have replaced Officer Dick.